This study assess ocular movements in a hand laterality judgment task in a population of musculoskeletal disorders. Reaction time, error rate and visual strategy are compared between musculoskeletal disorders and healthy patients, and between the different locations of the disorder.

Musculoskeletal disorders are a major public health issue. Recent studies showed that body schema alterations are involved in the chronification of those disorders. Those alterations bring the opportunity for new exploration or therapeutic solutions. Our hypothesis is that musculoskeletal disorders lead to motor imagery alterations relative to body schema disorders. Reaction time extension et error rate increase in a hand laterality judgment task would confirm that hypothesis. It is assumed that body schema alterations of patients suffering from musculoskeletal disorders could change with localisation, dependant on disorder's laterality and distality.

It is a monocentric, prospective, case-control trial, with 4 subgroups of 30 patients : shoulder rotator cuff tendinopathy, carpal tunnel syndrome, chronic low back pain, healthy subjects. We compare reaction time and error rate on a hand laterality judgement task. In that task, participants are asked to identify hand right or left laterality, when those hand is presented on a computer screen, by answering with the keyboard. Hands are shown on palmar or dorsal view and with 12 different angles of rotation. An eye-tracking device register participant eye movements during the task.

Inclusion Criteria:

• normal visual acuity
• social security affiliation
• signing consent
• rotator cuff tendinopathy, chronic low back pain, carpal tunnel syndrome or healthy subject

Exclusion Criteria:

• recent trauma or surgery
• psychiatric or neurological disorder
• psychotropic consumption
• previous experience with motor imagery
• bad french comprehension
• protected persons
• other painful affection than the inclusion criteria

patients refered to the Hospital University of Angers or the Hand Center in Trelazé for one of the musculoskeletal disorders meeting the inclusion criterias.